NCDView tutorial:
At the matlab prompt, start NCDView:
>> ncdv
From here all is done with the NetCDF file air.2m.gauss.2002.nc, from the NCEP Reanalysis.
Available free at:
ftp://ftp.cdc.noaa.gov/Datasets/ncep.reanalysis/surface_gauss/air.2m.gauss.2002.nc (51M).
Step 12 (velocity field) uses the NCEP Reanalysis files uwnd.10m.gauss.2002.nc and vwnd.10m.gauss.2002.nc,
available at:
ftp://ftp.cdc.noaa.gov/Datasets/ncep.reanalysis/surface_gauss/uwnd.10m.gauss.2002.nc (51M)
ftp://ftp.cdc.noaa.gov/Datasets/ncep.reanalysis/surface_gauss/vwnd.10m.gauss.2002.nc (51M)
I will call these three files, file_temp, file_u and file_v.
tutorial:
- load file_temp: menu file --> load
- select variable air: menu <3-D> --> air
- change range: click in the first > button to start at the
first index in the first dimension. You should now have something like this
- change gui size: menu misc --> gui size --> horiz +25%.
Result here
- use X and Y variables: if you check the menu <1-D> you will find the variables lon and lat.
Edit these names in the X and Y edit boxes. Select the associated checkbox and press
display. Result here
- overlay world coastline: menu misc --> overlay --> WCL 0:360.
Result here
- change line color and width: right mouse click over the coastline and select LineWidth 2 and
color black.
Result here
- keep this overlay: menu misc --> overlay --> always.
Now clicking in the first > button
to change time index will make new plot
with this overlay.
- keep zoom: press axis equal, press zoom and make Italy zoom.
Now select misc --> set limits --> all.
Result is like this
- see evolution of zoomed region: click in the first > button to change time index.
You will see always the zoomed area.
If misc --> set limits --> all was not done we would obtain something
like in step 6.
Now just uncheck the checkboxes in the bottom right corner (xlim, ylim, zlim and dataAspectRatio) and
press display.
You will obtain same as in 6 (but with axis equal)
- see evolution (until end of index): selecting menu misc --> auto>< , a dialog
box will appear where you can select the dimensions where automatic evolution will be applied.
Select the first (I) and press OK.
In the first dimension edit boxes put a step of 100 and press >.
Before, better activate the caxis checkbox, so that caxis be the same through the animation.
So, now you have see the evolution with a step of 100 until the end of first dimension
- velocity field: load file_u; load file_v; go to menu NCDV --> files and choose
the file [2] (file_u).
Go till menu <3-D> --> uwnd.
Now in the variables name edit box (first, at the top left corner), is written uwnd(2). Now, you should
add ',vwnd(3)', so that in this box must be written uwnd(2),vwnd(3).
Edit the 2nd and 3rd dimension edit boxes putting there a step of 3 in each.
Press display; now you may click press > as you wish,
considering you already unchecked I in the dialog misc --> auto>< .
But scale seems not ok, so go to scale and offset edit boxes and insert half of the value you find.
A good thing to do also before next > is to freeze xlim and ylim by activating
the xlim and ylim checkboxes. After all here is the result
- get result in normal window: to print the result better to copy the image to another figure
Use the button free and you will get this
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